Abstract

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In controlling E. coli infections antibiotics that were once effective are now ineffective due to the bacteria acquired resistance to these antibiotics. This research is carried out to characterize and identify Escherichia coli isolated from edible cockle (Senilia senilis) by molecular methods and screened for the presence of blaTEM gene that confer resistance to Extended spectrum β-Lactam antibiotics. The study was carried out from January to June 2020 at the Department of Microbiology, Rivers State University, Port Harcourt, Nigeria and the E. coli isolates were subjected to multiple antibiotic susceptibility test using Kirby-Bauer disc diffusion method and resistant isolates were screened for the presence of the resistance gene blaTEM). This screening was carried out via the process of DNA extraction, quantification, amplification of the gene using appropriate primer and agarose gel electrophoresis which showed the DNA extracts that had blaTEM genes when amplified. Forty (40) E. coli were isolated and identified culturally and molecularly from Senilia senilis. Results showed the presence of blaTEM gene in 5 out of the eight (8) isolates screened for blaTEM gene. Results also revealed that 52.5% of isolates had MAR index greater than 0.2 indicating high source of contamination where antibiotics are often used. Molecular characterization via sequencing of the 16S rRNA gene of the Seven (7) most resistant isolates confirmed that the isolates were strains of Escherichia coli. This study demonstrated the resistance ability of E. coli and the main factor behind its resistance. Further investigation into antimicrobial resistance is recommended for the administration of drugs most especially for the treatment of food-mediated E. coli infections.

Keywords: blaTEM, Escherichia coli, Molecular Characterisation, Resistant genes and Senilia senilis